1 What is mineral? "A mineral is an element or chemical compound that is normally crystalline and that has been formed as a result of geological processes"(Nickel,E.H.,1995). "Minerals are naturally-occurring inorganic substances with a definite and predictable chemical composition and physical properties."(O'Donoghue, 1990). A mineral is a naturally occurring homogeneous solid,inorganically formed,with a definite chemical composition and an ordered atomic arrangement" (Mason,et al,1968). "A mineral is an element or chemical compound that is normally crystalline and that has been formed as a result of geological processes" (Nickel, E. H., 1995).  "Minerals are naturally-occurring inorganic substances with a definite and predictable chemical composition and physical properties." (O' Donoghue, 1990).  A mineral is a naturally occurring homogeneous solid, inorganically formed, with a definite chemical composition and an ordered atomic arrangement" (Mason, et al, 1968). 1 What is mineral?